Re: " on the house"

: what is the meaning of " on the house" ?
From the Oxford English Dictionary: "on the house: at the expense of the tavern, saloon, etc.; also transf. and fig. (orig. U.S.)...
1889 Kansas City (Missouri) Times & Star 30 Nov., The first drink Thursday was 'on the house' in the leading saloons. 1891 Times 12 Sept. 10/3 A tied house..is one..owned by a brewer for the sale of his goods. 1934 J. A. LEE Children of Poor 26 'I must have a drink.' Here, have one on the house. 1944 AUDEN For Time Being 77 A voice I'd heard before, I think, Cried: 'This is on the House.' 1958 M. DICKENS Man Overboard xiii. 214 Laundry and cleaning were on the house. 1959 N. MAILER Advts. for Myself 95 One night just for the hell of it he has one on the house with the society gal, and she gets pregnant. 1967 W. SOYINKA Kongi's Harvest 18 Daodu:... Naturally it's on the house. Secretary: No, thank you. I prefer to pay for my drinks.

Among these citations, the M. DIckens quote is an example of transferred or figurative meaning, and others probably are as well, in which the "house" is the host, and "on the house" just means "free of charge" or "my treat."
SS